Same here as Scottsweet and Mitch. Not too much to do maintenance wise, biggest step was just getting it all setup. I'm really happy with the system.
I've had my Alkatrinic for roughly 2 years and dosetronic for about a year. I've done 1 ph probe change (~20 minutes the first time) and changed dosing pump tubes a few times (~3 minutes each). Calibration doesn't need to happen that often and quick to do.
The biggest hassle for me is making the testing solution. I have a one gallon jug and the solution lasts about 2 months. I always seem to notice it is low, just as I'm getting for take a trip. Considering the 10 minutes it takes me to remake it, there is no comparison to the 360+ alk. test I get out of it.
After an ATO and controller, its the best addition I've made to my tank.